As optical disks, ones constituted from an optical disk substrate made of a polycarbonate, an information recording layer formed on the optical disk substrate, and a protective film bonded to the information recording layer by an adhesive layer are generally known. In the case that the optical disk is read only, a concavo-convex pattern constituting pits is formed on the information recording layer, and in the case that the optical disk is rewritable, a concavo-convex pattern constituting grooves and lands is formed on the information recording layer.
As a method of forming such an information recording layer, for example a method is known in which a photocurable film (corresponding to a stamper-receiving layer) made of a photocurable resin is laminated onto an optical disk substrate made of a polycarbonate, next a stamper is pressed against the photocurable film, and in this state the photocurable film is cured by irradiating with light, and then the photocured film and the stamper are separated from one another, and a light-reflecting layer is formed on the embossed surface of the photocured film (Japanese Patent No. 2956989).
Moreover, as a method of bonding a protective film and an information recording layer together, for example a method is known in which a photocurable resin is coated onto the protective film or the information recording layer to form an adhesive layer, and then the protective film and the information recording layer are stuck together using this adhesive layer (Japanese Patent Application Laid-open No. 10-283683).
Such a photocurable resin shrinks during the curing reaction upon irradiation with light, and due to this cure shrinkage of the photocurable resin, there have been a problem of the adhesive strength of the stamper-receiving layer to the optical disk substrate, or the adhesive strength of the adhesive layer to the protective film or the information recording layer dropping, and hence the layers peeling away from one another during production of an optical disk or during storage of a produced optical disk, and a problem of warping of obtained optical disks occurring.